rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=decc/1/0x4000000000000000 softirq=15058/15058 fqs=0
rcu: 	(detected by 0, t=10505 jiffies, g=7421, q=557 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6055 Comm: syz.1.41 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:check_preemption_disabled+0x47/0x120
Code: 07 65 8b 0d bb ee 25 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 9b ee 25 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e <41> 5f 5d e9 81 ca 02 00 cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7
RSP: 0018:ffffc900001e07e0 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 0000000000000802 RCX: a0694d5d97502200
RDX: 0000000000010000 RSI: ffffffff8be34260 RDI: ffffffff8be34220
RBP: ffffc900001e0918 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200003c100 R12: dffffc0000000000
R13: ffffffff81ada91e R14: ffff888136627a98 R15: 1ffff9200003c110
FS:  00007fa76aff66c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2e9d5e CR3: 0000000027b78000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 rcu_is_watching+0x15/0xb0
 lock_release+0x4b/0x3e0
 _raw_spin_unlock_irqrestore+0x70/0x110
 hrtimer_try_to_cancel+0x3be/0x420
 hrtimer_cancel+0x3b/0x50
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3c5/0x550
 __hrtimer_run_queues+0x4e0/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:kmem_cache_alloc_noprof+0xef/0x3c0
Code: 00 00 41 83 fc ff 74 1a 48 8b 03 48 83 f8 ff 0f 84 d3 02 00 00 48 c1 e8 3a 41 39 c4 0f 85 5d 01 00 00 41 8b 46 28 4a 8b 1c 28 <49> 8d 4f 08 49 8b 36 4c 89 e8 4c 89 fa 65 48 0f c7 0e 74 5c eb 95
RSP: 0018:ffffc90004bafc38 EFLAGS: 00000246
RAX: 0000000000000400 RBX: ffff888110392a80 RCX: ffffffff92a33bd0
RDX: 0000000000000000 RSI: 0000000000000800 RDI: ffffffff8e25a320
RBP: 0000000000000cc0 R08: 0000000000000000 R09: ffffffff821661ad
R10: dffffc0000000000 R11: fffffbfff33ff99d R12: 00000000ffffffff
R13: ffff888110393300 R14: ffff888105627140 R15: 0000000000001129
 sk_prot_alloc+0x57/0x220
 sk_alloc+0x3a/0x370
 unix_create1+0xb0/0x7c0
 unix_create+0x16b/0x210
 __sock_create+0x4b3/0x9f0
 __sys_socketpair+0x1c5/0x560
 __x64_sys_socketpair+0x9b/0xb0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa76cd8ec29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa76aff6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007fa76cfd5fa0 RCX: 00007fa76cd8ec29
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000001
RBP: 00007fa76ce11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa76cfd6038 R14: 00007fa76cfd5fa0 R15: 00007ffc6627e9e8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g7421 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=2243
rcu: rcu_preempt kthread starved for 10505 jiffies! g7421 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:27240 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
